Ive got the rrod? What to do?

Yesterday I was about to play a game when my xbox 360 just froze a couple minutes in and gave me the 3 blinking red lights. I tried it again with a different game and it worked for the rest of the night but anytime after that I get the rrod. Its not the power... I got it refurbished online for dirt cheap and it has worked perfectly so far so I got my moneys worth but I dont want to go get a new one or anything. I dont know if i am technically enough to fix it myself and dont want to pay for a guide online. Since i got it refurbished then the warranty is definitely shot and I am not payin 100 to send it in to Microsoft. I just want to fix it or figure out a way to get a new 360 console for as cheap as possible.